Sensors are used for measuring quantities and/or converting the measured quantities into a signal which can be read by an observer and/or an instrument. Sensors may operate in high temperatures and/or other harsh environments, such as, for example, industrial equipment, rotor shafts, rolling bearings, helicopter blades, and/or wind turbine blades, etc.
Due to the varying environments in which measurements are taken, a number of different types of sensors have been developed, such as, for example, passive sensors and contactless sensors. Passive sensors may not have a power source to emit a signal, but rather passively accept incoming signals. Contactless sensors may wirelessly transmit the acquired data, therefore not being connected through a wire to a central monitoring station.
Sensors are typically called upon to exhibit a relatively high sensitivity over a large area of measure while maintaining a low cost of manufacture. The sensitivity and cost of manufacture of a sensor may depend upon the type of material and upon the method of fabrication used to manufacture the sensor, for example.
Some previous sensors may be able to operate in high temperatures and/or other harsh environments. However, such previous sensors had low sensitivity and/or a prohibitively high cost of manufacture due, in part, to the method of fabrication used to manufacture the sensors. That is, such previous sensors did not provide an adequate degree of measurement sensitivity and/or were prohibitively expensive to manufacture.